arch/.unmaintained/m68k-emul/permit.s

   1 /*
   2     Copyright © 1995-2001, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: Exec function Permit
   6     Lang: english
   7 */
   8
   9 /******************************************************************************
  10
  11     NAME
  12         AROS_LH0(void, Permit,
  13
  14     LOCATION
  15         struct ExecBase *, SysBase, 23, Exec)
  16
  17     FUNCTION
  18         This function activates the dispatcher again after a call to Permit().
  19
  20     INPUTS
  21
  22     RESULT
  23
  24     NOTES
  25         This function preserves all registers.
  26     EXAMPLE
  27
  28     BUGS
  29
  30     SEE ALSO
  31         Forbid(), Disable(), Enable()
  32
  33     INTERNALS
  34
  35     HISTORY
  36
  37 ******************************************************************************/
  38
  39         #include "machine.i"
  40
  41         .text
  42         .balign 16
  43         .globl  AROS_SLIB_ENTRY(Permit,Exec)
  44         .type   AROS_SLIB_ENTRY(Permit,Exec),@function
  45 AROS_SLIB_ENTRY(Permit,Exec):
  46 #if !UseRegisterArgs
  47         /* Preserve used registers */
  48         move.l  %a6,-(%sp)
  49
  50         /* Get SysBase */
  51         move.l  8(%sp),%a6
  52 #endif
  53
  54         /* Decrement and test TDNestCnt */
  55         subq.b  #1,TDNestCnt(%a6)
  56         jbpl    .noswch
  57
  58         /* return if there are no delayed switches pending. */
  59         btst    #7,AttnResched+1(%a6)
  60         jbeq    .noswch
  61
  62         /* if IDNestCnt is not -1 taskswitches are still forbidden */
  63         tst.b   IDNestCnt(%a6)
  64         jbpl    .noswch
  65
  66         /* Unset delayed switch bit and do the delayed switch */
  67         bclr    #7,AttnResched+1(%a6)
  68 #if !UseRegisterArgs
  69         move.l  %a6,-(%sp)
  70 #endif
  71         jsr     Switch(%a6)
  72 #if !UseRegisterArgs
  73         addq    #4,%sp
  74 #endif
  75
  76         /* all done. */
  77 .noswch:
  78 #if !UseRegisterArgs
  79         move.l  (%sp)+,%a6
  80 #endif
  81         rts
  82